Apparatus for and method of generating steam



Dec. 9, 1930. GLElCHMANN 1,784,426

APPARATUS FOR AND METHOD OF GENERATING STEAM Fi led June 4. 1927Patented Dec. 9, 1930 UNITED STATES PATENT OFFICE HANS GLEICHMANN, OFBERLIN-SIEMENSSTADT, GERMANY, ASSIGNOB TO SIEMENS- SG HUCKERTWERKEGESELLSCHAFT MIT BESCHRANKTER HAF'IUNG, OF SIEMENSSTADT, GERMANY, ACORPORATION OF GERMANY,

BERLIN- ATPABATU'SFOR AND "METHOD GENERATING STEAM Application filedJune 4, 1927, Serial No. 196,593, and in Germany June 9, 1926.

My invention relates to anapparatus for and a method of generatingsteam.

My invention consists in highly preheating the working medium by wasteheat and then evaporating it by superheating heat, which is withdrawnfrom the working medium, itself heated beyond the working temperature.

An embodiment of my invention is illustrated by way of example in thedrawing affixed hereto.

In the drawings Fig. 1 represents a heat diagram explanatory oftheworking of my improved process.

Fig. 2 represents an apparatuspartly in diagram and partly in verticalsection for carrying out my improved process, and

Fig. 3 represents a modification of the apparatus shown in Fig. 2.

Referring to the heat diagram in Fig. -1 of the drawing P denotes thetemperature of the water at which it is introduced into the apparatus inwhich the waste heat is recovered. The waste heat may either becontained in the steam withdrawn (regenerative process), or it may beflue gas heat, or the water may be preheated by steam and flue gases incombination. The preheating is carried as far as possible and reachesits highest point at V. It will now be assumed that the apparatus isalready inoperation, i. e. that a portion of the working medium issuperheated to the point T and that T is the temperature at which theworking medium is introduced into the power engine. Before the workingmedium reaches the power engine it is, according to the invention passedat the temperature T into a heat exchange apparatus in which it heatsthe water, already preheated to the point V, up to the point K and,since the point K is the critical point, converts it steadily i. e.without ebullition, into steam. The area 2 V K 3 in the diagram shouldthus be equal to the area 4 T T 5. The furnace alone consequentlysugplies theheat 3 K T 5 only.

Referring to ig. 2 of the drawing, IS a pump, 11 a receptacle into whichthe preheated water is introduced, 12 a heat exchange device consistingof'tubes. 13,15 and 17 are the connecting tubes, 14; is the superheaterlocated in a combustion chamber 19, 20 is a receptacle containing waterand being arranged behind the superheater and swept and heated by theflue gases flowing past it, 21 is a feed water supply pipe and 22 asupply pipe to the receptacle 11. 16 are the headers forv the tubes 12,18 is a turbine and 23 an electric generator.

The manner of operation of the apparatus is as follows: the pump 10conveys the water, highly preheated in the receptacle 20, into thereceptacle 11, which is heated by the heat exchange device 12. The steamgenerated thereby in the receptacle 11 flows through the pipe 1& to asuperheater 14 in which it reaches, for instance, the temperature T Thesuperheater 14 is heated in a combustion chamber 19 by means of anysuitable fuel, such as coal, pulverized coal or gas. The pipes 15 leadthe superheated steam into the headers 16 with which the heat exchangetubes 12 are in communication. In this tubular heat exchange device thetemperature of the steam traversing it is lowered to the value T owingto the transfer of heat to the contents of the receptacle 11 and thencethe steam at reduced superheating temperature T passes through the livesteam pipe 17 to the consumer, for instance the turbine 18, driving theelectric generator 23.

I Fig. 3 of the drawings, illustrating a modification of the apparatusaccording to Fig. 2, shows the essential modified parts only. The waterreceptacle2O is here not located within the reach of the flue gases ofthe combustion chamber 19 but a coil 25 traversing it is incommunication with a turbine 18 by means of a pipe 24. The exhaust steamof the turbine 18 flows through this coil within the water receptacle 20and heats the feed water.

The preheated water is conveyed in exactly the same manner as in Fig. 2into the receptacle 11 by means of the pump 10 across the connectingpipe 22.

From the coil the steam may be passed into the condenser 26 and thecondensed steam may in its turn be usedfor feeding the faces only andthe further advantage is obtained that the deposits of sludge in thetubes 12 is harmless since these tubes are not exposed to the fire andmay easily be cleaned and renewed.

Various changes and modifications may be made Without departing from thespirit of my invention and I desire therefore, that only v suchlimitations shall be placed thereon as are imposed by the prior art.

I claim as my invention: 1; An apparatus for generating steam comprisinga superheater and means for externally supplying heat to saidsuperheater, a

steam generating receptacle located outside of said external heat supplymeans, and a heat exchange device contained in said reccptacle, saidexchange device beingconnected at one end to the output side of saidsuperheater, and at the other end to a steam main, said heat exchangedevice supplying to the liquid contained in the receptacle all of theheat necessary to evaporate the liquid, and a steam connection betweenthe steam space of said receptacle and the input side of saidsuperheater.

2. The method of indirectly generating vapor used by a consumer, whichconsists 1n contlnually supplying and evaporating a highly preheatedliquid operating medium,

superheating the. vapor generated by direct outside heat supply, and inbringing the superheated vapor into heat transferring contact with thepreheated liquid medium before the vapor reaches the consumer, theentire heat necessary for said evaporation'being transferred to thepreheated liquid medium from the amount of said superheated vaporactually used by the consumer.

3. The method of indirectly generating steam used by a consumer, whichconsists continually in generating steam under critical conditions fromcontinually supplied water,

, highly preheated by Waste heat, superheating the generated steam bydirect outside heat supply and in bringing the superheated steam intoheat transferring contact with the preheated water before the steamreaches the consumer, whereby the entire heat necessary for said steamgeneration is supplied to the preheated water from the amount of saidsuperheated steam actually used by the consumer.

In testimony whereof I afiix my signature.

HANS GLEICHMANN.

